Across
- 1. World Health Organization
- 5. Organ for thought
- 7. Green, photosynthetic plant part
- 9. Hard, dense body tissue
- 10. Infectious agent
- 11. Biological catalyst
- 13. Messenger in protein synthesis
- 15. Organ for gas exchange
- 16. Plant's upright support
- 17. Bird's jaw
Down
- 2. Type of plant used for flavour or medicine
- 3. Basic unit of life
- 4. Cell division type
- 6. Heredity unit
- 8. Animal life
- 10. Blood carrier returning to the heart
- 12. Plant-like organisms in water
- 13. Below-ground plant part
- 14. Smallest unit of a chemical element
- 16. Largest organ of the human body